Meanwhile, DSS exposure accelerated the differentiation of Hlf+ hematopoietic stem and progenitor cells (HSPCs) into monocytes and enhanced their recruitment to the injured colon (Figure S9P, Supporting Information).[53, 54] Compared with Osx‐cre;Ccl2fl/+ mice, Osx‐cre;Ccl2fl/fl mice exhibited significantly less weight loss, reduced colon shortening and improved histological outcomes (Figure 6E–I), indicating that Ccl2 deletion from BM‐MSCs attenuated colitis. The gene discussed is CCL2; the disease is colitis.